Structure and Function of Membrane-Derived Oligosaccharides of Escherichia coli. The cell envelope of E. coli and other gram-negative bacteria contain a group of glucose-containing oligosaccharides substituted with sn-1-glycerophosphate and phosphoethanolamine residues derived from the head groups of membrane phospholipids. It is proposed to elucidate the chemical structure of these oligosaccharides, and to investigate their metabolism and function. Intracellular Transport of Phospholipids in Hepatocytes. Mechanisms for the translocation of phosphatidylcholine in isolated hepatocytes will be investigated, with particular attention to the postulated role of specific phospholipid exchange proteins. Structure of an Intrinsic Membrane Protein: Phosphatidylserine Decarboxylase. This membrane protein contains a covalently bound pyruvate residue, the location of which in the protein will be determined. The source of the puruvate residue will also be investigated. Search for Phospholipoproteins in E. coli. Experiments with labeled glycerol and glycerophosphate will be carried out to determine whether E. coli contains protein with covalently bound phospholipid, as is the case with the extracellular penicillinase of Bacillus licheniformis. If such phospholipoproteins are found, their possible role in the translocation of proteins across the cytoplasmic membrane will be studied.